This invention relates to a disposable pull-on garment which absorbs and retains excrements.
Japanese Patent Application Publication No. 1995-236650A discloses a disposable pull-on diaper which comprises a liquid pervious top sheet, a liquid impervious back sheet and a liquid absorbent core interposed between those two sheets, with respective longitudinal side edges of front and rear waist-encircling regions being secured to each other to provide a waist-encircling opening and a pair of leg-encircling openings. In the front waist-encircling region, a plurality of waist elastic members extending in a waist-encircling direction are secured in an extended state to an edge portion of the waist-encircling opening. To an edge portion of each leg-encircling opening, a plurality of leg elastic members are secured in an extended state extending in a leg-encircling direction. Also, a plurality of auxiliary elastic members extending in the waist-encircling direction between the longitudinal side edges of the front and rear waist regions are secured in a region between the waist elastic members and the leg-encircling opening edge portions.
Each auxiliary elastic member has an extensible portion and a non-extensible portion. The extensible portion extends from longitudinal side edges of the core positioned over the front and rear waist-encircling regions toward respective longitudinal side edges of the front waist-encircling region. The non-extensible portion traverses the core to extend between opposite longitudinal side edges of the core. The extensible portions of the auxiliary elastic members act to tighten a wearer""s waist so that the diaper while in use is prevented from sliding down from its position. In the non-extensible portions of the auxiliary elastic members, the diaper is not subjected to a tensile stress from the auxiliary elastic members which may otherwise cause the core to contract, so that the core is prevented from puckering.
The diaper disclosed in the above Publication relies solely on the extensible portions of auxiliary elastic members to prevent its downward slide and accordingly requires an increase in tensile stress of the auxiliary elastic members in their extensible portions. The diaper is thus pressed strongly against the wearer""s waist, making the wearer uncomfortable. The non-extensible portions of the auxiliary elastic members do not act to press the core against the wearer""s skin. This increases the possibility of the core being spaced from the wearer""s skin in use, and accordingly adversely affects the excrement-absorbing function of the core.
It is an object of this invention to provide a disposable pull-on garment which, in use, is not pressed locally against a waist region of the wearer and does not adversely affect the function of the core to absorb excrements.
The present invention provides a disposable pull-on garment having a waist-encirclable direction and a longitudinal direction orthogonal to the waist-encirclable direction. The garment comprises a liquid-pervious topsheet, a liquid-impervious backsheet and a liquid-absorbent core interposed between the topsheet and backsheet to define front and rear waist-encirclable regions and a crotch region extending between the front and rear waist-encirclable regions. The respective longitudinal side edges of the front and rear waist regions are joined together in the longitudinal direction to define a waist-encirclable opening and a pair of leg-encirclable openings. Waist-encirclable elastic members are attached to respective edge zones of the waist-encirclable opening in the front and rear waist-encirclable regions. There are provided plural lines of auxiliary elastic members, which extend in the waist-encirclable direction and are arranged to be spaced at distances from each other in the longitudinal direction in a region defined between the waist-encirclable elastic members and the leg-encirclable openings in at least one of the front and rear waist-encirclable regions. At least one of the front and rear waist-encirclable regions has first elasticized zones and a second elasticized zone, wherein the second elasticized zone traverses a portion of the core in that region and extends in the waist-encirclable direction between opposite longitudinal side edges of the portion of the core, and wherein the first elasticized zones extend in the waist-encirclable direction outwardly from the longitudinal side edges of the portion of the core, respectively, to the adjacent one of the longitudinal side edges of the associated waist-encirclable region. The auxiliary elastic members include plural lines of first and second auxiliary elastic members, the first auxiliary elastic members being positioned in the first elasticized zones, the second auxiliary elastic members being non-continuous with the first auxiliary elastic members and being positioned in the second elasticized zone. A tensile stress of the first elasticized zone is greater than that of the second elasticized zone.
In accordance with a first aspect of the present invention, a tensile stress of the first auxiliary elastic members is greater than that of the second auxiliary elastic members.
In accordance with a second aspect of the present invention, the number of the first auxiliary elastic members is larger than that of the second auxiliary elastic members.
According to one exemplary embodiment of the present invention, each first elasticized zone when extended to its maximum extent exhibits a tensile stress in a range of 0.2-2.0 N/25 mm, and the second elasticized zone when extended to its maximum extent exhibits a tensile stress in a range of 0.1-0.6 N/25 mm.